<!DOCTYPE html>
<html>
<head>
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<style>
* {
  box-sizing: border-box;
}

.header {
  border: 1px solid red;
  padding: 15px;
}

.row::after {
  content: "";
  clear: both;
  display: table;
}

[class*="col-"] {
  float: left;
  padding: 15px;
  border: 2px solid blue;
}

.col-1 {width: 8.33%;}
.col-2 {width: 16.66%;}
.col-3 {width: 25%;}
.col-4 {width: 33.33%;}
.col-5 {width: 41.66%;}
.col-6 {width: 50%;}
.col-7 {width: 58.33%;}
.col-8 {width: 66.66%;}
.col-9 {width: 75%;}
.col-10 {width: 83.33%;}
.col-11 {width: 91.66%;}
.col-12 {width: 100%;}
</style>
</head>
<body>

<div class="header">
  <h1>Shanghai</h1>
</div>

<div class="row">

<div class="col-3">
  <ul>
    <li>The Flight</li>
    <li>The City</li>
    <li>The Island</li>
    <li>The Food</li>
  </ul>
</div>

<div class="col-9">
  <h1>The City</h1>
  <p>Shanghai is one of the four direct-administered municipalities of the People's Republic of China. Welcome to Shanghai!
</p>
  <p>请调整浏览器窗口的大小，以查看内容如何响应调整大小。</p>
</div>

</div>

</body>
</html>
